Parapneumonic effusion

Parapneumonic effusion (PPE) refers to an exudative pleural effusion associated with pulmonary infection.

Approximately 40% of patients who are hospitalised for pneumonia develop a PPE 3.

Fluid leaks into the pleural space due to increased permeability of the visceral pleura adjacent to the infected lung.

Bacterial pneumonias are a more common cause of PPEs than viral pneumonias 3

Chest radiograph and CT

Similar findings to a simple pleural effusion 1:

Parapneumonic effusions often resolve with the treatment of the underlying pneumonia. However, ~7.5% of patients with PPE progress to a fibrinopurulent stage such as empyema 3

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Article information

rID: 30524
System: Chest
Section: Pathology
Synonyms or Alternate Spellings:
  • Parapneumonic effusions
  • Parapneumonic effusion (PPE)

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Cases and figures

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    Case 1
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    Case 2: pneumococclal pneumonia
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